Contents
DIODES PAM2304 EVB Board
Revision Information
| Date | Revision | Description | Comment |
| 2011/01 | V1.0 | Initial release | |
PAM2303 General Description
The PAM2304 is a step-down current-mode, DC-DC converter. At heavy load, the constant frequency PWM control performs excellent stability and transient response. To ensure the longest battery life in portable applications, the PAM2304 provides a power -saving Pulse-Skipping Modulation (PSM) mode to reduce quiescent current under light load operation to save power. The PAM2304 supports a range of input voltages from 2.5V to 5.5V, allowing the use of a single Li+/Li-polymer cell, multiple Alkaline/NiMH cell, USB, and other standard power sources. The output voltage is adjustable from 0.6V to the input voltage, while the part number suffix PAM2304-XX indicates pre-set output voltage of 3.3V, 2.8V, 2.5V, 1.8V, 1.5V, 1.2V or adjustable. All versions employ internal power switch and synchronous rectifier to minimize external part count and achieve high efficiency. During shutdown, the input is disconnected from the output and the shutdown current is less than 1uA. Other key features include under-voltage lockout to prevent deep battery discharge. The PAM2304 is available in SOT23-5 packages.
Key Features
- Efficiency up to 94%
- 40uA(TYP.) Quiescent Current
- Internal Synchronous Rectifier
- 3MHz Switching frequency to minimize inductor value
- Soft Start
- Under-Voltage Lockout
- Short Circuit Protection
- Up to 1A output current
- Thermal Shutdown
- 5-pin Small SOT23-5 Package
- RoHS Pass and Green Package
EV Board Schematic
EVB PAM2304 EB11AA Description
PAM2304 EB11AA is an evaluation board for the PAM2304, a 3MHz DC/DC converter. The board is targeted to be used in providing a simple and convenient evaluation environment for the PAM2304. Requires parts, power supply jacks etc. on the board, which makes it easy to be evaluated. This application note contains new product information. Diodes, Inc. reserves the right to modify the product specification without notice. No liability isassumed as a result of the use of this product. No rights under any patent accompany the sale of the product.
EV Board View
Top View
EV board operational sequence:
- Connect power supply to VIN and GND.
- Connect load to VO and GND.
- Connect EN to high to enable the chip.
- This demo board output current is up to 500mA.
EV Board BOM List
| Item | Value | Type | Rating | Description | Vender and Part No. |
| C1 | 10µF | X5R/X7R, Ceramic/0805 | 10V | Input coupling CAP | JMK212BJ106MA |
| C2 | 10µF | X5R/X7R, Ceramic/0805 | 10V | Input coupling CAP | JMK212BJ106MA |
| C3 | 100pF | NPO/COG, 0603 | 50V | Forward CAP | UMK105 CG101JV-F |
| L1 | 1µH | 1008 | 0.5A | Inductor | Wurth 74479787210 |
| IC1 | PAM2304 | SOT-23-5 | Power management IC | PAM2304 | |
| PCB | PAM2304 EB11AA 20*12mm |
External Compnents Selection
Input & output Capacitors (C1, C2)
- For lower output ripple, low ESR is required.
- Low leakage current needed, 10uF, X5R/X7R ceramic recommend
Feed forward capacitor (C3)
- Lower the output ripple
- Low leakage current needed, 20-100pF, NPO/COG ceramic recommend
Output Voltage programmer resistors (R1, R2)
- For programmer output voltage
- For accurate output voltage, 1% tolerance is required.
Inductor (L1)
- Low DCR for good efficiency
- Inductor rated Current must higher than the output current